1 /*
2 * Copyright (C) 2006 James Livingston <doclivingston@gmail.com>
3 *
4 * This library is free software; you can redistribute it and/or
5 * modify it under the terms of the GNU Library General Public
6 * License as published by the Free Software Foundation; either
7 * version 2 of the License, or (at your option) any later version.
8 *
9 * This library is distributed in the hope that it will be useful,
10 * but WITHOUT ANY WARRANTY; without even the implied warranty of
11 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
12 * Library General Public License for more details.
13 *
14 * You should have received a copy of the GNU Library General Public
15 * License along with this library; if not, write to the
16 * Free Software Foundation, Inc., 51 Franklin St, Fifth Floor,
17 * Boston, MA 02110-1301, USA.
18 */
19
20 /**
21 * SECTION:element-vorbistag
22 * @title: vorbistag
23 * @see_also: #oggdemux, #oggmux, #vorbisparse, #GstTagSetter
24 *
25 * The vorbistags element can change the tag contained within a raw
26 * vorbis stream. Specifically, it modifies the comments header packet
27 * of the vorbis stream.
28 *
29 * The element will also process the stream as the #vorbisparse element does
30 * so it can be used when remuxing an Ogg Vorbis stream, without additional
31 * elements.
32 *
33 * Applications can set the tags to write using the #GstTagSetter interface.
34 * Tags contained withing the vorbis bitstream will be picked up
35 * automatically (and merged according to the merge mode set via the tag
36 * setter interface).
37 *
38 * ## Example pipelines
39 * |[
40 * gst-launch-1.0 -v filesrc location=foo.ogg ! oggdemux ! vorbistag ! oggmux ! filesink location=bar.ogg
41 * ]|
42 * This element is not useful with gst-launch-1.0, because it does not support
43 * setting the tags on a #GstTagSetter interface. Conceptually, the element
44 * will usually be used in this order though.
45 *
46 */
47
48 #ifdef HAVE_CONFIG_H
49 # include "config.h"
50 #endif
51
52 #include <glib.h>
53 #include <gst/tag/tag.h>
54 #include <gst/gsttagsetter.h>
55
56 #include <vorbis/codec.h>
57
58 #include "gstvorbistag.h"
59
60
61 GST_DEBUG_CATEGORY_EXTERN (vorbisparse_debug);
62 #define GST_CAT_DEFAULT vorbisparse_debug
63
64 static GstFlowReturn gst_vorbis_tag_parse_packet (GstVorbisParse * parse,
65 GstBuffer * buffer);
66
67 #define gst_vorbis_tag_parent_class parent_class
68 G_DEFINE_TYPE_WITH_CODE (GstVorbisTag, gst_vorbis_tag,
69 GST_TYPE_VORBIS_PARSE, G_IMPLEMENT_INTERFACE (GST_TYPE_TAG_SETTER, NULL));
70
71 static void
gst_vorbis_tag_class_init(GstVorbisTagClass * klass)72 gst_vorbis_tag_class_init (GstVorbisTagClass * klass)
73 {
74 GstVorbisParseClass *vorbisparse_class = GST_VORBIS_PARSE_CLASS (klass);
75 GstElementClass *element_class = GST_ELEMENT_CLASS (klass);
76
77 gst_element_class_set_static_metadata (element_class,
78 "VorbisTag", "Formatter/Metadata",
79 "Retags vorbis streams", "James Livingston <doclivingston@gmail.com>");
80
81 vorbisparse_class->parse_packet = gst_vorbis_tag_parse_packet;
82 }
83
84 static void
gst_vorbis_tag_init(GstVorbisTag * tagger)85 gst_vorbis_tag_init (GstVorbisTag * tagger)
86 {
87 /* nothing to do */
88 }
89
90
91 static GstFlowReturn
gst_vorbis_tag_parse_packet(GstVorbisParse * parse,GstBuffer * buffer)92 gst_vorbis_tag_parse_packet (GstVorbisParse * parse, GstBuffer * buffer)
93 {
94 GstTagList *old_tags, *new_tags;
95 const GstTagList *user_tags;
96 GstVorbisTag *tagger;
97 gchar *encoder = NULL;
98 GstBuffer *new_buf;
99 GstMapInfo map;
100 gboolean do_parse = FALSE;
101
102 gst_buffer_map (buffer, &map, GST_MAP_READ);
103 /* just pass everything except the comments packet */
104 if (map.size >= 1 && map.data[0] != 0x03)
105 do_parse = TRUE;
106 gst_buffer_unmap (buffer, &map);
107
108 if (do_parse) {
109 return GST_VORBIS_PARSE_CLASS (parent_class)->parse_packet (parse, buffer);
110 }
111
112 tagger = GST_VORBIS_TAG (parse);
113
114 old_tags =
115 gst_tag_list_from_vorbiscomment_buffer (buffer, (guint8 *) "\003vorbis",
116 7, &encoder);
117 user_tags = gst_tag_setter_get_tag_list (GST_TAG_SETTER (tagger));
118
119 /* build new tag list */
120 new_tags = gst_tag_list_merge (user_tags, old_tags,
121 gst_tag_setter_get_tag_merge_mode (GST_TAG_SETTER (tagger)));
122 gst_tag_list_unref (old_tags);
123
124 new_buf =
125 gst_tag_list_to_vorbiscomment_buffer (new_tags, (guint8 *) "\003vorbis",
126 7, encoder);
127 gst_buffer_copy_into (new_buf, buffer, GST_BUFFER_COPY_TIMESTAMPS, 0, -1);
128
129 gst_tag_list_unref (new_tags);
130 g_free (encoder);
131 gst_buffer_unref (buffer);
132
133 return GST_VORBIS_PARSE_CLASS (parent_class)->parse_packet (parse, new_buf);
134 }
135